* throws an {@code IllegalStateException}.)
   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */
  @SuppressWarnings({"AndroidJdkLibsChecker", "Java7ApiChecker"})
  @IgnoreJRERequirement // Users will use this only if they're already using streams.
  @Beta // TODO: b/288085449 - Remove.
  public static <T extends @Nullable Object, K, V>
      Collector<T, ?, ImmutableMap<K, V>> toImmutableMap(

  /**
   * @since 21.0 (but only since 23.5 in the Android <a
   *     href="https://github.com/google/guava#guava-google-core-libraries-for-java">flavor</a>).
   *     Note, however, that Java 8+ users can call this method with any version and flavor of
   *     Guava.
   */
  @Override
  @CheckForNull
  public final V getOrDefault(@CheckForNull Object key, @CheckForNull V defaultValue) {
    /*